KPE 365 Ch 6

Movements in infancy

- are not random they are coordinated - Play a role in future movement, create the foundations of future movements

Changes in individual constraints that occur in typically developing infants

- maturation of the central nervous system - development of muscular strength and endurance - development of posture and balance - improvement of sensory processing

How can we tell primitive reflexes from spontaneous movements?

- reflexes are the responses to specific external stimuli whereas spontaneous movements do not result from any apparent external stimuli - reflexive movements are specific and often localized whereas spontaneous movements tend to be nonspecific and generalized - the same stimulus will elicit a specific reflex over again and again

First child syndrome

A cultural phenomenon where first time mothers hold their infant for long periods and avoid putting the infants on their stomachs for a long time, results in delayed onset of certain motor milestones like crawling, the infant does not have the opportunity to strengthen her neck muscles when lying prone

Pathological cerebral condition

A reflex that persists well after the average age of disappearance may indicate...

Postural reactions

A.k.a. gravity reflexes, help the infant automatically maintain posture in a changing environment, some of these responses keep the head upright and the breathing passages open or help the infant rollover

cocontraction

Activating the muscles for flexing and extending the limb

Infantile reflex

An involuntary stereotypical movement response to a specific stimulus; the term refers specifically to such responses seen only during infancy. The three types are primitive and locomotor reflexes and postural reactions

babinski reflex

Checking a reflex by running a probe along the bottom of the patients foot, used to check for neurological problems in patients with head injuries, when the reflex is present the patient most likely has a central nervous system injury

Applied theories of reflexes

Examine the role of reflexes in future volitional movement, like walking

There is no secular trend in milestones

Infants are currently attaining motor milestones at about the same age as infants did more than 80 years ago

Motor milestone sequence

Is fairly predictable in typically developing infants and although variability exists in the acquisition of milestones, substantial delay in several milestones may indicate a developmental problem

Motor milestone

Landmarks in motor development; a fundamental motor skill whose attainment is associated with the acquisition of later voluntary movements. The order in which infants attain these milestones is relatively consistent, although the timing differs among individuals

The rate controlling factor in infant posture and balance

May be a coupling of the sensory information with the appropriate motor response a.k.a. sensorimotor coupling

Locomotor reflexes

Reflexes that appear similar and are related to a voluntary movement (swimming, stepping, crawling), these reflexes appear much earlier than the voluntary behaviors and disappear before the infant tries the voluntary skill

stereotypies

Rhythmic flapping arms and kicking of legs; have underlying temporal structure

Functional explanation of reflexes

Suggests that reflexes exist to help the infants survive, to eat, breathe, and grasp

Moving room

Technique used to make it seem as if the body is moving

Optical flow

The change in optic patterns while one moves

stepping

The increase and decrease of _____________ with changes in environmental and task constraints (increasing leg weight adding a treadmill) indicate that systems other than the nervous system must be involved in this aspect of motor development

Motor interference

Theory that says that infants cannot move voluntarily until reflexes have been inhibited by the Central nervous system`

Structural explanation of reflexes

Views reflexes as a byproduct of the human neurological system, the way humans are wired

spontaneous mvoements

aka stereotypies; movements that occur without any apparent stimulation; ex. squirm, thrust arms and legs

Primitive reflex

an involuntary response to specific stimulation which is often mediated by lower brain centres; these reflexes tend to lose their strength overtime

supine kicking

spontaneously thrusting legs while lying on back; rhythmic and coordinated, resembles walking pattern

Infant movements

though not always goal directed or goal achieving can be coordinated and the coordination patterns may resemble patterns seen in adults